1. Field of the Invention
The present invention relates to a motorcycle-use power unit including a crankcase which constitutes a portion of an engine body mounted on a vehicle body frame. A clutch device is arranged in a power transmission passage between the crankshaft and a drive wheel so as to engage or disengage the transmission of rotational power of the crankshaft which is rotatably and pivotally supported on the crankcase toward the drive wheel. A clutch cover is joined to either one of left and right side surfaces of the crankcase in a state that the crankcase is mounted on the vehicle body frame so as to form a clutch chamber which houses the clutch device between the clutch cover and the crankcase. A clutch control device performs a changeover of engagement and disengagement of the clutch device.
2. Description of Background Art
JP-A-2006-117174 discloses a motorcycle-use power unit in which a clutch control device which performs a changeover of engagement and disengagement of a clutch device is arranged in a space surrounded by seat rails of a vehicle body frame which supports an engine body.
In the structure of the power unit disclosed in JP-A-2006-117174, which arranges the clutch control device in a state wherein the clutch control device is surrounded by the seat rails, it is necessary to remove a rider's seat supported on the seat rails in performing the maintenance of the clutch control device. Thus, there exists a drawback that the maintenance of the clutch control device cannot be easily performed. Further, a pipe which connects the clutch device and the clutch control device with each other is elongated thus giving rise to drawbacks wherein a weight of the motorcycle is increased and, at the same time, the transmission efficiency of an oil pressure is lowered.